1. Field of the Invention
The invention is generally directed towards improvements in an apparatus for mounting marker light and telemetry equipment to railroad cars, and more particularly, to an improved apparatus for securing equipment to the guard arm side of a coupler head on the last car in a train wherein the apparatus includes a means for simultaneously locking the equipment to the coupler head and locking a compartment door on the equipment.
2. Description of the Prior Art
The preferred method for meeting modern railroad operating and safety requirements is by using end of train monitoring and signalling equipment mounted on the last car in a train. The equipment typically monitors brake line pressure, and may also monitor train movement and train light operation, as well as a variety of other variables. The monitored information is then transmitted to the head of the train by a battery powered telemetry transmitter. In addition to its monitoring functions, the equipment provides a marker light which identifies the end of the train. The light must be positioned a certain height above the track and meet certain dispersion characteristics as required by governmental regulations.
Several methods for securing end of train signalling and monitoring equipment to the coupler head of the last car in a train have been devised. U.S. Pat. No. 2,355,544 to McGowan and U.S. Pat. No. 4,487,060 to Pomeroy show signalling and monitoring equipment positioned within the coupler opening. The problem with this arrangement is that the coupler containing the equipment cannot mate with a coupler on another railroad car without damaging the equipment. Moving trains around in an active yard can often lead to damaged equipment simply because railroad personnel have forgotten to remove the equipment from the coupler. Moreover, a pusher locomotive cannot be connected to the rear of the train without having to remove the signalling and monitoring equipment first.
The problem of avoiding accidental damage was addressed in U.S. Pat. No. 4,592,217 to Fernandez et al which shows the signalling and monitoring equipment mounted on the top surface of the coupler head. In the Fernandez et al patent, the supporting frame includes an integral rod which extends through the flag hole in a railroad coupler. Hence, two cars can be coupled without any damage to the equipment. However, not all couplers are fabricated with a flag hole and, therefore, the Fernandez et al mount cannot be used on all railroad cars.
The guard arm side of a coupler head is generally fabricated with four relief holes. The relief holes facilitate the casting of the coupler head and lighten the coupler. U.S. Pat. No. 4,520,662 to Schmid discloses a coupler mount which includes a pair of jaws that are clamped to the four relief holes of a coupler head. The coupler mount is installed on a coupler head by inserting two pairs of parallel jaw members into the relief holes and drawing the jaw members together by rotation of a rod. The Schmid mount allows the coupler head on which it is mounted to be mated to another train's coupler without damage to the signalling and monitoring equipment positioned on the mount; however, the Schmid mount is expensive to manufacture and is difficult for one man to attach to a railroad car coupler head.
In U.S. Pat. No. 4,691,563 to Martin, a railroad coupler mount which utilizes two of the four relief holes in the guard arm side of a coupler head is disclosed. The mount comprises a banana shaped arm member which extends through two relief holes that are on a common horizontal axis. A padlock is secured through a portion of the arm which projects from the relief holes at a first end. The mount is then tightened against the coupler head by a screw clamp arrangement positioned at the second end of the arm which draws the arm back out of the relief holes until the padlock is tightly braced against the guard arm side of the coupler head.